Sulfur containing organosilicon compounds are useful as reactive coupling agents between rubber and silica fillers providing for improved physical properties. They are also useful as adhesion primers for glass, metals and other substrates.
U.S. Pat. Nos. 3,842,111, 3,873,489 and 3,978,103 disclose the preparation of various sulfur containing organosilicon compounds. These organosilicon compounds are prepared by reacting
(a) 2 moles of a compound of the formula EQU Z-Alk-hal PA1 where hal is a chlorine, bromine or iodine; Z is ##STR3## where R.sup.1 is an alkyl of 1 to 4 carbon atoms or phenyl and R.sub.2 is alkoxy of 1 to 8 carbon atoms; or cycloalkoxy of 5 to 8 carbon atoms; or alkylmercapto with 1 to 8 carbon atoms; Alk is a divalent aliphatic hydrocarbon or unsaturated hydrocarbon or a cyclic hydrocarbon containing 1 to 18 carbon atoms; with PA1 (b) 1 mole of a compound of the formula EQU Me.sub.2 S.sub.n PA1 where Me is ammonium or a metal atom and n is a whole number from 2 to 6.
Japanese Patent Application No. 124400-1984 and U.S. Pat. No. 4,820,751 each disclose a rubber composition containing a silicate-based filler and a compound containing siloxy groups and a benzothiazole group. One example of such compound is trimethyoxysilylpropyl-mercaptobenzothiazoletetrasulfide.